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In the present work, the microstructure, crystal orientation, mechanical properties and strengthening mechanisms for different regions of WE71 cylindrical parts have been investigated. The results showed that from inner wall to outer wall, second phases density, DRX fraction decreased but average grain size increased, which is well agree with the strain state and metal flow during back extrusion. For compression area, α//ED texture type can be found in region a, but α directions deflects from ED to TD at a certain angle for region b and c. For shear area, α directions deflects from ED to TD about 10°~45°. For stable forming area, the texture is close toα//ND. After peak ageing, a large number of nanometer scaled β' phases were formed and uniformly distributed in the Mg matrix, while zigzag GP zone and RE-hexagons precipitates can also be found in the peak-aged alloy. Tensile properties for region c in compression area are the lowest: UTS, YS and EL are 322 MPa, 215 MPa and 2.5%, respectively. Furthermore, for the stable forming area, the UTS, YS and EL of 283 MPa, 187 MPa and 19% in the region f are the highest, but the strength of region g is the lowest, which is related to the grain size and volume fraction of second phases on flow lines. The strengthening contributes from fine-grain strengthening, texture strengthening and Orowan strengthening.

In order to accumulate experience in the design and manufacturing of the toroidal field coils for the China Fusion Engineering Test Reactor, a model coil of mixed Nb3Sn-NbTi superconducting magnet with a maximum magnetic field variation rate of 1.5 T/s has been developed at the Institute of Plasma Physics, Chinese Academy of Sciences. The preload system, as one of the key components of the model coil, plays a crucial role in maintaining the overall integrity and stability of the model coil. First the magnetic field and electromagnetic forces of the model coil under extreme conditions are calculated based on Maxwell's equations. Then, the mechanical performance of the model coil at room and cryogenic temperatures is analyzed. To addressing the issue of excessive stress in the preload components of the model coil under preload, several optimization design schemes are proposed and iteratively analyzed. Finally, stress linearization is performed, and stress evaluation is conducted based on the analytical design. The assessment results indicate that certain optimization schemes enable the preload components to fully meet the operational requirements at both room and cryogenic temperatures. The outcomes presented in the paper will provide reference for the subsequent design and manufacturing of the central solenoid coil.

Aiming at obtaining ultra-low kinematic stiffness and improving the isolation property of low frequency vibration, it is necessary to solve the coupling parameters and rated load of air negative pressure characteristics and rubber characteristics, in order to achieve an ideal elastic characteristic curve of air negative pressure spring. Firstly, the background and working principle of the negative pressure rubber isolation were introduced. In addition, the FEA model of isolator is built based on Mooney-Rivlin constitutive model of rubber. Furthermore, to testify the validity of the mathematical model, the static characteristic and simulation analysis of isolator are studied. The experimental data and characteristic curve of different negative pressure were obtained, the simulated results show a good agreement with those of corresponding experiments. Finally, they also illustrate the validity of the vibration isolation, which realizes better performance of low-frequency vibration isolation.

The article deals with the analysis of the structure and fracture surface of aluminum alloy samples. Alu-minum alloy AlMg9 was used as an experimental material. The material from which the samples were made was supplied as cast without heat treatment, and specifically the material was produced by the continuous casting method. The structure of the test material was examined using a Neophot 32 optical microscope, and the fracture surface of the test sample was examined using a scanning electron microscope (SEM). The fatigue life of the aluminum alloy was tested by three-point bending cyclic loading using the parameters - frequency f = 100 Hz, temperature T = 22 ± 5 ℃ and stress ratio R = 0.11. The analysis showed that cast aluminum alloys are very sensitive to casting defects, such as porosity or the content and distribution of intermetallic phases. If large pores or phases are present on or near the surface of the sample, this can be the dominant cause of fatigue crack initiation and reduction of the fatigue lifetime.

Even today, there is an ever-increasing demand for the production of aerosol cans made of aluminium, as the cosmetics and other propellant-enriched products stored in them reach more and more people with the development of humanity. The production of these packaging materials is primarily carried out by plastic forming operations. However, during the production process of aluminium aerosol cans, tools with a defined edge geometry also perform cutting operations. The processes taking place here affect the quality of the final product. In this paper, the procedure and results of finite element modelling of the flange turning of aluminium aerosol cans is presented. The structure of the finite element model is introduced, as well as the possibilities of considering the peculiarities of the process. Since the used pure aluminium (Al99.5) is considered a difficult-to-cut material, the machinability of aluminium and its alloys is also discussed.

Today's milling cutting tools are produced in various types and shapes for a wide variety of machining processes. Development continues and offers new technological solutions. The design of replaceable milling heads offers a significant cost reduction, as only the worn-out part is replaced instead of the en-tire tool. The tough connection between the tool and the shank achieves stable performance in roughing and finishing milling. Because of the possibility of using different milling inserts, the number of neces-sary tools will also be reduced and the flexibility of using milling tools will increase. The article exam-ines the cutting forces when machining a milling head produced by additive technology and made of Onyx material, which is reinforced with carbon fibre.

Conventional spinning is one of the oldest processes used widely in manufacturing to obtain cup shape products. Conventional spinning is the technique that produce axisymmetric part or component over rotating mandrel with the help of rigid tool known as rollers. The shape of roller is very important parameter for the success of the spinning process. This paper datils about using ball shaped rollers as forming tool in conventional spinning process experimentally. The experimental work was carried out on the center lathe machine as forming machine, the spinning tool or spinning rollers was installed on a dynamometer replaced the tool post while the mandrel was mounted on the lathe chuck. The spinning tool in this work consists of three rollers performing the conventional spinning. The set of rollers is mounted on jaws of lathe chuck which working as a holder for the spinning tool parts. The experimental work was conducted in order to test the proposed tool and investigate the influence of the main conventional spinning parameters (mandrel rotational speed, axial feed and blank diameter or spinning ratio) on the process forming load and the product quality. The response of the product quality and required load to process parameters such as rotational speed (76,150, 230 and 305 rpm), axial feed (0.08, 0.15,0.3, and 0.6 mm/rev) also examined new rollers in different mandrel diameters 45, 60 and 80 mm. The experimental results showed that, the suggested tool acquired a spinning ratio of 2.17 which is about 35% greater than the announced conventional spinning ratio of 1.6 without any addition to the tool just using the suggested Ball shaped roller arrangement. the mandrel rotational speed, and axial feed rate are the most pronounced parameters, which have great effects on the forming loads during the spinning process.

Article deals with processing of intermetallic materials produced by powder metallurgy M390 and M398 Microclean® produced by Böhler. Main interest is the analysis & measurement of their surface rough-ness and topography after the processing by DNMG and WNMG geometry of cutting inserts with 0.4 and 0.8 mm radius after hard turning at the same process parameters for both materials and all types of cutting inserts. The comparative studies were carried out for the microgeometrical and chip formation research on the machined surfaces and the technological processes were assessed, including chip dia-grams. Spectral analysis was used to verify the composition of investigated materials by spectral analysis measuring device. In order to examine the surfaces in detail, in addition to the standard roughness measurement, surface topography was performed by the coherent correlation interferometric micro-scope. The results of surface roughness as well as topography show higher wear resistance of M398 ma-terial compared to M390. This was confirmed indirectly by the fact that it is primarily shown by the higher surface roughness of M398 after machining under the same conditions. These properties are ob-tained by a higher content of additive elements, respectively of their carbides. Based on the conclusions of these experiments, additional knowledge and recommendations for the processing of these materials were created.

The paper presents the results of measurement uncertainty obtained with a tool probe for 4 cutting tools with different values of the nominal radius rf = {3,4,5,7} mm. The tool probe was used to collect experimental data enabling the evaluation of the uncertainty budget of the measuring system. The evaluation was made based on a statistical analysis of measured tool radius values. Each radius value was determined by 30 repetitions of tool probe measurement. The mean value and the standard uncertainty of obtained results were determined. Assuming that the expansion factor was k=2, the expanded uncertainty U was determined, its value ranging between 0.00142 mm and 0.00462 mm for the tested tool radius values. The standard uncertainty ranged from 0.00081 to 0.00231 mm. According to the manufacturer's specifications, the standard uncertainty of the probe is 0.0015 mm.

The electrochemical discharge machining (ECDM) process is developing into a potentially useful method of performing micromachining in conductive or non-conductive materials. The materials are machined using a combination of chemical and thermal energy. This paper examines the effect of Artificial Neural Network (ANN) architectures combined with particle swarm optimization (PSO) on the predictive ability of tungsten carbide machining. Material removal rate (MRR) and surface roughness (SR) is the response used to evaluate the performance of the ECDM process. The four selected process parameters are voltage, gap width, electrode type, and type of electrolyte, with each parameter has two levels. The 4-9-1 structure was chosen to obtain pre-dictions in the form of an optimal formula based on the statistical values for surface roughness: MSE 0.001, RMSE 0.025, MAPE 1.36, and R2 0.99.

Additive Manufacturing has enabled the design of complex components in several technical fields. Considering turbomachinery components, additive manufacturing has unlocked the achievement of significant performances for dynamic rotoring components. The application of topology optimization methods is one of the main factors accelerating the technological development of this sector. This paper presents a procedure for the optimization of static turbomachinery components. The frame-work proposed compares the results obtained by introducing a lattice structure and a solid optimized shape. The procedure is presented with reference to a specific case study. To validate the proposed framework, the complete re-design of a thrust collar of a major Italian-based Oil&Gas company is carried out, demonstrating that the re-thinking of the component in terms of Topology Optimization is a straightforward approach to increase the overall performance of the produced part.

The presented work deals with the study of the effect of increasing the doses of irradiation by accel-erated electrons on the sliding properties of polymer materials. Due to the influence of radiation, sur-face roughness changes occur on the surface of the experimental materials, which lead to changes in the properties of the coefficient of friction on the selected polymer materials. Three types of polymer materials PET, PTFE and PE2000C were used for the experimental research, which, due to their properties, are used for different types of sliding products. A steel ball of G40 material was used as a pressure material, which moved along a linear path on which the load was increased from 10 N to 100 N. Electron beam accelerators with the conversion of electrons to X-rays combine the advantages of a high ability to penetrate gamma photons sources and high performance of electron beam devices. The application possibilities of the device are wide due to the dual mode of operation (electron beam or X-ray beam) and a wide range of applicable doses and also dose rates.

With regard to the current economic situation, which deals primarily with energy prices, companies are trying to find reserves within individual technologies. The automotive industry is still a very important industry. One of the ways to improve the material properties of a body part is thermomechanical processing. This is how the B-pillar, which serves as a safety structural element of the car, was processed. The presented article aims to investigate the influence of selected thermomechanical processing parameters on the resulting properties of a B-pillar made of high-strength steel 22MnB5. At the same time, energy saving in the given production process should be used in such a way that it is not at the expense of the quality of the component. Three kinds of experimental production processes with different parameters of thermomechanical processing of steel were proposed for scientific investigation. Based on these proposed processes, several pieces of B-pillars were produced and subjected to further investigation. Changes in material properties were monitored using hardness measurements and subsequently the resulting microstructure of the material was examined for each experimental post.

Twinning induced plasticity (TWIP) steels are a class of high-strength steels that have been devel-oped for their outstanding ductility and strength properties. TWIP refers to the fact that these steels display an unusually high degree of deformation before fracture due to the formation of twins during deformation. TWIP steels could be used in a variety of industries for structural applications or com-ponents that need to withstand high levels of stress and deformation. This article deals with the de-velopment of high strength with fully austenitic microstructure and high chromium content. Micro-structure, mechanichal and corrosion properties of this steel were studied.

The presence of reinforcing particles SiCp seriously affects the cutting surface quality of SiCp/Al materials.In this study, different machining parameters were tested to obtain good surface quality, and the surface quality of SiCp/Al alloy material under different milling parameters was studied by using the surface profilometer and scanning electron microscope to explore the effect of cutting pa-rameters on surface quality. The results showed that the Surface roughness value increased with the increase of feed rate and milling speed, and milling speed was the dominant factor in the microstruc-ture evolution of the machined surface. In addition, an exponential model related to feed rate and milling speed was constructed.

Nowadays, the digitalization of the production process is an indispensable part of the stampings production in the pre-series stage, but also as a subsequent support for series production. Automotive producers are under pressure to comply with the ever decreasing CO2 production standards for cars, which predicates the use of modern material types with an advantageous weight-to-strength ratio. This paper focuses on the use of mathematical modelling in a numerical simulation environment to predict the deformation process and subsequent material spring-back of dual-phase steel DP500. The material data and characteristics are used to define the material computational model in numerical simulation. The results of the numerical simulations are then compared with the stamping obtained by a real pressing process, where their shape comparison and further evaluation of the used material models and selected parameters are performed.

The condition for the designability and efficiency of the machining processes is that the part production process is chosen to meet the operational requirements based on the most accurate technological plans possible. One part of this is the planning of the required quality and roughness of the surfaces and achievement of the required values in the finishing. In this paper, a study on the predictability of surface roughness was performed using a CAD model based on theoretical roughness and validated by cutting experiments. The reported results show the effect of the feed rate change in face milling for two tools with different edge geometries in planes parallel to the feed direction.

There is a lot of applications for manipulating industrial robots nowadays. Maximizing the tasks that can be assigned to robot manipulators is one of the criteria for deciding if their application is appropri-ate. The article discusses the topology optimization of the gripping jaws of an industrial robot to reduce the jaws' weight. The previously used gripping element made of C50E steel was optimized to reduce the weight of the jaws. Shape optimization was performed based on analysis from CAD programs Inventor Professional 2022, Autodesk Fusion 360, and Ansys Discovery. The new jaws were manufactured by the additive technology of selective laser sintering (SLS) from PA12 material. The optimization resulted in a significant reduction in weight compared to the original jaws. As a result of optimizing the weight of the designed jaws, it was possible to increase the weight of the object of manipulation.

Precision mirror mould CNC machining is a technology of great importance in industrial manufacturing. Precision mirror moulds are usually used to produce high-precision, high-quality parts and products, which are widely used in automotive manufacturing, aerospace, electronic equipment and other industries. However, the traditional mould polishing process often fails to meet the manufacturing needs of precision moulds, so the application of CNC machining technology has become an effective way to solve this problem. Through the use of CNC machine tools and computer control systems, etc., the detailed formulation of the process plan, so that precision mirror mould CNC machining can achieve high efficiency, accuracy and stability of the machining process, to improve the quality and productivity of the mirror mould. Therefore, the applied research on CNC machining of precision mirror mould is of great significance and economic value.

This paper presents a new method of improving the material removal process in metal cutting. Chip formation plays an important factor in the metal cutting process and increasing its condition has a great impact on cutting machine details. Based on lubricating cooling conditions in the metal cutting process, a novel methodology is proposed to decrease the deformation that emerged in the material removal process while cutting cylindrical details in lathes. Application of stating magnetic field on flowing cutting fluids decreased the shrinkage of the chip in turning operation. Analytical and practical experiments show that the effect of cutting fluid under the influence of a static magnetic field decreased the shrinkage of the chip up to 20 % in comparison to the conventional use of cutting fluids in turning cylindrical pars with HSS tools.

As a gas storage container, gas cylinders have been widely used in industry, mining, military, medicine, diving, automobiles and other fields. The gas cylinder produced by spinning can fundamentally eliminate the defects related to the weld in the traditional production process. In order to explore the metal flow law of cylinder closure spinning, its finite element simulation is established and carried out by using ABAQUS/explicit software. The influence of the parameters such as angle radius R and screw wheel installation angle on the metal flow field and wall thickness distribution are studied and revealed.

The paper is focused on the dynamic response of a Hybrid III crash-test dummy during low-severity frontal (forehead) and side (temple) head impacts. The measurements used a pedestrian dummy (Hybrid III 50th percentile male dummy, Jasti Co., ltd., Tokyo, Japan) and a unique pendulum impact testing machine (impactor) of own design and construction. The tests were conducted at two various impact intensities (velocities) that did not exceed the speed of 1.6 m.s^-1. The primary outcome variable was a resultant magnitude of acceleration measured on the vertex of the dummy’s head and the results were compared to 11 human volunteers. The goal of the study was to analyze the biofidelity of the Hybrid III Dummy in a pedestrian setting during low-severity frontal and side head impacts by comparing the dynamics and kinematics of the dummy’s head to human volunteers.

The growing use of composite materials in various industries implies the necessity of conducting research on both their manufacture and subsequent machining. One of the main problems in composite machining is the selection of a suitable cutting tool. This study investigates the effect of the geometry and material of a milling cutter on the quality of a milled composite part. A carbon fiber-reinforced epoxy resin matrix composite was tested. Two cutting tools were used: an end mill with PCD inserts with a diameter of 12 mm and the number of teeth of 3 as well as a PCD-coated carbide end mill with a diameter of 12 mm and the number of teeth of 4. Variable technological parameters were used. The quality of the machined surfaces was assessed based on burr height and selected profile roughness parameters. Results showed that for the milling process conducted with the same technological parameters, the surface quality obtained with the 4-tooth PCD-coated carbide tool was higher than that obtained with the 3-tooth tool with PCD inserts.

The work deals with the possibility of using additive technology in the production of positioning and clamping device. The designed clamping device will facilitate and accelerate the measurement of samples with inclined or different irregular surfaces. The designed device is manufactured by additive technology using composites. Onyx material reinforced with Kevlar fibers was used as material for composite printing. The designed device should achieve the required properties for the firm and stable clamping of the components during the measurement process, and its weight should be significantly reduced with the use of composite material.

In order to cultivate students' professional skills and enhance students' practical ability, this paper proposes to create a virtual simulation experiment system of NC machine tool based on SolidWorks software platform, taking vertical machining center as the research object, which is integrated by three modules of NC machine tool structure, machine tool operation and machine tool processing. Firstly, the detailed assembly relationship of each subsystem of the machine tool, the assembly rela-tionship of the overall equipment and the system composition are displayed intuitively by 3D modeling, so that students can understand the 3D modeling method and structure composition of complex CNC machine tools. Secondly, according to the machining process characteristics of vertical machining center, using typical parts to create the virtual simulation platform to carry out complex parts programming and machining methods and steps based on vertical machining center. Through the full combination of virtual simulation experiment and actual equipment, it has significant results in improving students' interest in learning, ensuring teaching effect, reducing material waste, avoiding machine tool accidents and so on. And combined with the actual processing, operation of CNC machine tool experiment to achieve the combination of virtual and real, vivid image, rigorous and realistic, open and sharing, expand the numerical control technology class teaching and talent training. It also provides a good reference for similar curriculum development.

Fisheye contact pair is an important component of board level interconnection products wide range of applications. However, insertion and withdrawal force have great influence on the contact deformation due to their small size and complex structure. In this paper to the fisheye contact pairs of interconnection products as the research object, the main parameters were analyzed which could affect the contact deformation of fisheye structure, and factor analysis of them were performed. And three relatively more significant factors were extracted. The simulation based on Response Surface Methodology (RSM) is designed, And the experimental data was conducted regression fitting, getting the second regression model. The established quadratic regression model was analyzed based on MATLAB and the response of various factors on the insertion and withdrawal force, then the optimized parameter model of fisheye structure was obtained. The research shows that the quadratic regression model based on response surface methodology fitting accuracy was high and there were good practical value about it.

The main aim of this article is to show the possibilities of using tram windscreen impact tests in the analysis of human-machine accidents. Empirical experience shows that these accidents especially affect the head, which is at the same time one of the most vulnerable parts of the human body. Windscreen safety testing follows ECE standards and, inter alia, involves collisions with a headform. With regards to numerical simulations, however, it is essential to be able to determine the material characteristics of windscreens. Here it seems to be advantageous in terms of validity, reliability and the economic cost of using collisions with a rigid body where only the glass absorbs all of the kinetic collision energy. The outcome of these tests is a waveform of the cont act force's magnitude as a function of deformation in the direction the force acts. Along with the time course of acceleration of the bumper and its kinetic energy on impact, this information can serve as boundary conditions to verify mathematical models.

This paper deals with a synthesis of a new ionising radiation attenuation composite material from Lu2O3 - Bi2O3 nanoparticles structure, that has never been described yet. The paper describes the preparation of Lu2O3 - Bi2O3 nano- and microparticles by three methods: a self-combustion synthesis, a solid-state method and a coprecipitation method. Polymer solution was prepared from Lu2O3 - Bi2O3 nanoparticles and Polyvinyl Butyral. Afterwards, nanofibers were processed by an electrospinning method from PVB - Lu2O3 - Bi2O3 polymer solution. PVB - Lu2O3 - Bi2O3 nanofibers were characterised and their X-Ray attenuation effect was tested. This paper proceeds from one of the author’s bachelor thesis.

The design of the formwork support for a certain section of the Beijing subway project was carried out in this paper. And the disk lock formwork support was used in the engineering.It was analyzed on the the design of the formwork support for the roof with the thickness of 1.5m of the interval engineering. The manual calculation and the sap2000 finite element analysis were also used in the paper.The effect of the diagonal brace and its number were analyzed in addition to the design of the formwork support. It was showed that the axial force of the standing tube tends to be uneven with the increase of the number of slant bars in the framework. And the axial force of the standing tube connected to diagonal brace is larger than that of the framework without brace significantly. So it will be dangerous to the framework without considering the effect of it by the manual calculation.

Three cutting technologies, plasma, laser, and acetylene, were used to produce the same geometry of a hole with 33 cm diameter. The plates of the same steel St-37 (1.0038, ČSN 11375) with a thickness of 50 mm were used in all three cases and the aim of the work was to evaluate and compare micro-structure changes of the cut surfaces. Longitudinal and transverse samples were taken from all cuts for subsequent analysis. Light and scanning electron microscopy of surface and below-surface areas were carried out at all samples. Hardness profiles were determined by micro-hardness and nano-hardness measurements. Based on these results, the depth of material that was influenced by cutting was established by image analysis of light micrographs, micro-hardness measurement and nano-hardness measurement. It was found out, that all three technologies influence significantly micro-structure and surface hardness of cut steel. Acetylene cutting resulted in the deepest affected zone consisting of several layers with gradually changing microstructures based on various ferritic-carbidic morphologies.